Renal biopsy in the elderly

Abstract

Introduction: Kidney disease is very common among the elderly. Over the last decades, the number of renal biopsies performed on these patients has increased. Objective: This study was carried out to examine the frequency and the clinical-pathological correlation of kidney disease in elderly patients who have had a renal biopsy done. Methods: The clinical presentation of kidney disease and the main histological findings were retrospectively analyzed in patients over 65 who had undergone renal biopsy (n=109) for a period of 12 years. Results: The total number of renal biopsies performed during this period was 871, out of which 109 (12.5%) corresponded to patients over 65. The main indications for renal biopsies were nephrotic syndrome (37.6%) and kidney failure (34.9%). Microscopic hematuria was found in 59.6% of the patients and high blood pressure in 62.4% of them. The most frequent histological diagnosis was membranous glomerulonephritis (21.1%), followed by extracapillary glomerulonephritis (20.2%). When clinical syndromes and histological findings were compared, the nephrotic syndrome was found to be the main feature of membranous nephropathy (78.3%), of focal segmental glomerulosclerosis (55.6%) and of diabetic nephropathy (66.7%). Kidney failure was present in 90% of the cases of extracapillary glomerulonephritis (95.5% pauciimmune or type 3). Microscopic hematuria was the main sign of mesangial prolifeative 
glomerulonephritis (83.3%). Conclusions: Nephrotic syndrome and kidney failure (especially rapidly progressive renal failure) were the main renal biopsy results in this group of patients, bearing close relation to histological findings. The most common types of glomerulonephritis were membranous GN and pauciimmune extracapillary GN. Renal biopsy provides useful information for the diagnosis, prognosis and treatment of kidney disease in the elderly.